Flush toilet

ABSTRACT

A flush toilet includes multiple discharge outlets formed in a rim part and provided to discharge flush water in one circumferential direction along an inner peripheral surface of the rim part, and, when a toilet bowl part is divided into four divided regions in plan view by a lateral center line, and a longitudinal center line, the multiple discharge outlets include a first discharge outlet provided in at least one of a first divided region and a second divided region, and a second discharge outlet provided in a third divided region, and a water discharge part is configured such that the amount of flush water discharged through the first discharge outlet is larger than the amount of flush water discharged through the second discharge outlet.

REFERENCE TO RELATED APPLICATIONS

This application is a national stage application under 35 USC 371 of International Application No. PCT/JP2017/002271, filed Jan. 24, 2017, which claims the priority of Japanese Application No. 2016-070587, filed Mar. 31, 2016, the entire contents of each of which are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a flush toilet.

BACKGROUND OF THE INVENTION

A study of flushing methods for flushing the toilet bowl part of a toilet has been conventionally conducted in various ways. Patent Document 1 proposes a flush toilet in which a first discharge outlet is provided in one of left and right regions on the rear side of the toilet bowl part, and a second discharge outlet is provided in the other of the left and right regions on the rear side of the toilet bowl part. In the flush toilet, a flow changing part is provided at a termination end part of a rim conduit, which leads flush water discharged through the second discharge outlet. By allowing the flush water to hit on the flow changing part, the flow of the flush water can be directed to a recess part provided in a bottom part of the toilet bowl part. Accordingly, it is considered that flush water with strong force can be made to flow into the recess part, thereby facilitating discharge of waste within the recess part and improving the waste discharge performance.

Patent Document 1 Japanese Unexamined Patent Application Publication No. 2012-202143

Meanwhile, on an inner peripheral surface of the toilet bowl part, there is generally provided, on the front side with respect to the recess part, a large curvature portion of which the curvature is larger than other portions provided continuously on the left and right sides. When the flush water discharged through the aforementioned first discharge outlet flows through the large curvature portion, the velocity component of the flush water in a circumferential direction of the toilet bowl part is reduced. As a result, the flush water discharged through the first discharge outlet is less likely to reach a surface region of the toilet bowl part located opposite, in a lateral direction, to the first discharge outlet with the recess part therebetween, so that it is difficult to ensure toilet bowl flushing capability, which is the capability of flushing the toilet bowl part. As a countermeasure thereto, if the total amount of flush water used for one toilet flushing process is increased, because of the centrifugal force applied to the flush water, the flush water may easily splash out when flowing through the front end part of the toilet bowl part. Accordingly, another idea for improvement is desired.

The present invention has been made in view of such a problem, and a purpose thereof is to provide a flush toilet with favorable toilet bowl flushing capability.

To solve the problem above, a flush toilet of one aspect of the present invention comprises a toilet body including a toilet bowl part, a rim part that forms a peripheral edge part of an upper opening of the toilet bowl part, and a water discharge part that discharges flush water into the toilet bowl part, wherein: the water discharge part includes a plurality of discharge outlets formed in the rim part and provided to discharge flush water in one circumferential direction along an inner peripheral surface of the rim part; when the toilet bowl part is divided into four divided regions in plan view by a lateral center line, which bisects a lateral dimension of an outer surface portion of the toilet body, and a longitudinal center line, which bisects a longitudinal dimension of an inner surface portion of the toilet bowl part, and when, with regard to the four divided regions, a rear-side divided region to which a front-side divided region is adjacent in the other circumferential direction is defined as a first divided region, and the three divided regions located subsequent to the first divided region in the one circumferential direction are serially defined as a second divided region, a third divided region, and a fourth divided region, the plurality of discharge outlets include a first discharge outlet provided in at least one of the first divided region and the second divided region, and a second discharge outlet provided in the third divided region; and the water discharge part is configured such that the amount of flush water discharged through the first discharge outlet is larger than the amount of flush water discharged through the second discharge outlet.

According to this aspect, a sufficient amount of flush water can be easily provided to the fourth divided region where the flush water discharged through the first discharge outlet is less likely to reach, so that favorable toilet bowl flushing capability can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment will now be described, by way of example only, with reference to the accompanying drawings which are meant to be exemplary, not limiting, in which:

FIG. 1 is a sectional side view of a toilet body according to the present embodiment;

FIG. 2 is a sectional plan view of the toilet body according to the present embodiment;

FIG. 3 is a diagram used to describe a lateral center line La of the toilet body and a longitudinal center line Lb of a toilet bowl part in the flush toilet;

FIG. 4 is a diagram that shows flows of flush water within the toilet bowl part of the flush toilet; and

FIG. 5 is a plan view that shows a magnified view of vicinity of a second discharge outlet of the flush toilet.

DETAILED DESCRIPTION OF THE INVENTION

In the following embodiment and modifications, same reference characters denote same constituting elements, and the repetitive description will be omitted. Also, in each drawing, part of the constituting elements may be appropriately omitted, or the size of a constituting element may be appropriately enlarged or reduced, for the sake of convenience. In the following, constituting elements having many features in common may be distinguished from each other by adding “first, second, third”, “left, right”, or the like at the beginnings of the names thereof and adding “-A, -B, -C”, “-L, -R”, or the like at the ends of the reference numerals thereof, and such distinguishing words and characters may be omitted when the constituting elements are collectively referred to.

FIG. 1 is a sectional side view of a toilet body 12 of a flush toilet 10 according to the present embodiment. FIG. 2 is a sectional plan view of the toilet body 12.

The flush toilet 10 comprises the toilet body 12 made of a ceramic material, a resin material, or the like. The toilet body 12 is formed such that, in plan view, the longitudinal dimension along a longitudinal direction is larger than the lateral dimension along a lateral direction. In the specification, the lateral direction and the longitudinal direction are perpendicular to each other in plan view. Although not illustrated, above the toilet body 12 are provided a casing, which houses a device for warm water washing, such as a pubic lavage device, and a toilet lid and a toilet seat, which are supported by the casing to be vertically rotatable. The toilet body 12 comprises a toilet bowl part 14, a drainage passage part 16, a rim part 18, and a water discharge part 20.

The toilet bowl part 14 is formed in a front part of the toilet body 12. The toilet bowl part 14 comprises a receiving surface part 22 of a bowl-like shape that receives waste, and a recess part 24 recessed downward from a lower edge part of the receiving surface part 22 and formed in a bottom part of the toilet bowl part 14. The receiving surface part 22 is formed into an elliptical shape of which the longitudinal dimension is larger than the lateral dimension in plan view. The receiving surface part 22 is formed such as to be inclined downward toward the center of the bowl. The recess part 24 is formed into a bottomed shape, and, on a bottom surface part thereof, an inlet 16 a of the drainage passage part 16 opens.

The drainage passage part 16 is connected to the bottom part of the toilet bowl part 14. The drainage passage part 16 is a passage for waste discharged from the toilet bowl part 14 to a sewage water passage (not illustrated). The drainage passage part 16 includes a trap part 28 in which seal water 26 is stored to block airflow in the water flowing direction. Part of the seal water 26 is stored within the recess part 24 of the toilet bowl part 14.

The rim part 18 forms a peripheral edge part of an upper opening 14 a of the toilet bowl part 14. The rim part 18 includes an inner peripheral wall part 18 a and an upper wall part 18 b. The inner peripheral wall part 18 a forms an upper end part of the inner peripheral wall part of the toilet bowl part 14 and is connected to an upper edge part of the receiving surface part 22. On the inner peripheral wall part 18 a, discharge outlets 30 and rim conduits 44, which will be described later, are formed. The upper wall part 18 b extends from the upper opening 14 a of the toilet bowl part 14 to both the left and right sides and also to both the front and rear sides of the toilet body 12.

In the flush toilet 10 of the present embodiment, the positional relationships of the constituting elements are determined in relation to a lateral center line La and a longitudinal center line Lb described below. FIG. 3 is a diagram used to describe the lateral center line La of the toilet body 12 and the longitudinal center line Lb of the toilet bowl part 14. The lateral center line La of the toilet body 12 is a straight line that extends along a longitudinal direction and bisects a lateral dimension Lx of an outer surface portion of the toilet body 12 in plan view. More specifically, in plan view, a straight line that bisects the lateral dimension Lx, which is the maximum dimension between a left end 12L and a right end 12R of the outer surface portion of the toilet body 12, is the lateral center line La. Also, the longitudinal center line Lb of the toilet bowl part 14 is a straight line that extends along a lateral direction and bisects a longitudinal dimension Ly of an inner surface portion of the toilet bowl part 14 in plan view. More specifically, in plan view, a straight line that bisects the longitudinal dimension Ly, which is the maximum dimension between a front end 14F and a rear end 14R of the inner surface portion of the toilet bowl part 14, is the longitudinal center line Lb. The intersection of the lateral center line La and the longitudinal center line Lb is the center point Cp of the toilet bowl part 14.

As shown in FIG. 2, the water discharge part 20 is provided to discharge flush water into the toilet bowl part 14. The water discharge part 20 includes multiple discharge outlets 30 and two water passages 32. The multiple discharge outlets 30 are formed on the inner peripheral wall part 18 a of the rim part 18. In the present embodiment, three discharge outlets 30 are formed. Through the multiple discharge outlets 30, flush water is discharged in one circumferential direction (the counterclockwise direction in FIG. 2 and, hereinafter, simply referred to as the counterclockwise direction) of the toilet bowl part 14 along the inner peripheral surface of the inner peripheral wall part 18 a of the rim part 18.

As shown in FIG. 3, the toilet bowl part 14 is divided by the lateral center line La and the longitudinal center line Lb of the toilet bowl part 14 into four divided regions Sr1-Sr4 in plan view. The four divided regions Sr1-Sr4 are different portions of the toilet bowl part 14 divided by the lateral center line La and the longitudinal center line Lb as the boundaries in plan view. In the following, with regard to the four divided regions, a rear-side divided region to which a front-side divided region is adjacent in the other circumferential direction (the clockwise direction in FIG. 3 and, hereinafter, simply referred to as the “clockwise direction”) of the toilet bowl part 14 is defined as a first divided region Sr1. Also, among the four divided regions, the three divided regions located subsequent to the first divided region Sr1 in the counterclockwise direction in plan view are serially defined as a second divided region Sr2, a third divided region Sr3, and a fourth divided region Sr4. The front-side divided regions are the second divided region Sr2 and the third divided region Sr3, and the rear-side divided regions are the first divided region Sr1 and the fourth divided region Sr4.

The multiple discharge outlets 30 include a first discharge outlet 30-A provided in the second divided region Sr2, a second discharge outlet 30-B provided in the third divided region Sr3, and a third discharge outlet 30-C provided in the fourth divided region Sr4. The first discharge outlet 30-A is disposed on one side in a lateral direction (the right side in FIG. 3), and the second discharge outlet 30-B and the third discharge outlet 30-C are disposed on the other side in the lateral direction (the left side in FIG. 3).

Also, the first discharge outlet 30-A is provided at a position as described below, in relation to an upper edge 34 of the receiving surface part 22. The upper edge 34 of the receiving surface part 22 includes, in plan view, a front region 34 a including a front end 34F, a rear region 34 b including a rear end 34B, and middle regions 34 c on the left and right sides, which each connect the front region 34 a and the rear region 34 b. On a vertical cross section that passes through the center point Cp of the toilet bowl part 14 (such as the cross section shown in FIG. 1), the upper edge 34 corresponds to the position of an inflection point, at which the bending direction of the inner peripheral surface of the toilet bowl part 14 changes from the radially inward direction to the radially outward direction, located midway from the receiving surface part 22 to the rim part 18. The front region 34 a has a curved shape of which the radius of curvature falls within a first range R1 (70 mm to 120 mm, for example), and the rear region 34 b has a curved shape of which the radius of curvature falls within a second range R2 (100 mm to 130 mm, for example). The middle regions 34 c are respectively positioned on the left and right sides of the center point Cp of the toilet bowl part 14 in plan view and each have a curved shape of which the radius of curvature falls within a third range R3 (200 mm to 530 mm, for example), which is greater than the first range R1 and the second range R2.

On the upper edge 34 of the receiving surface part 22, there are provided first curvature changing points 34 d, which each serve as a boundary between the front region 34 a and a middle region 34 c, and second curvature changing points 34 e, which each serve as a boundary between the rear region 34 b and a middle region 34 c. In such a situation, the first discharge outlet 30-A is provided between the first curvature changing point 34 d and the second curvature changing point 34 e, with regard to the position in a longitudinal direction of the toilet body 12. From another perspective, it can be said that the first discharge outlet 30-A is provided rearward of the first curvature changing point 34 d, with regard to the position in a longitudinal direction of the toilet body 12.

As shown in FIG. 2, the water passages 32 include a right water passage 32-R (first water passage) provided on one side in a lateral direction (the right side in FIG. 2) of the toilet body 12, and a left water passage 32-L (second water passage) provided on the other side in the lateral direction (the left side in FIG. 2). The right water passage 32-R is provided to supply flush water to the first discharge outlet 30-A, and the left water passage 32-L is provided to supply flush water to the second discharge outlet 30-B and the third discharge outlet 30-C. The right water passage 32-R is formed inside a right portion 18-R (a first portion), on which the first discharge outlet 30-A is provided, of right and left portions 18-R and 18-L of the rim part 18. Also, the left water passage 32-L is formed inside the left portion 18-L (a second portion), on which the second discharge outlet 30-B is provided, of the right and left portions 18-R and 18-L of the rim part 18. The left water passage 32-L is provided such as not to lie across the lateral center line La of the toilet body 12, on the front side of the toilet bowl part 14. The right portion 18-R of the rim part 18 means a portion located on the right side, as one of left and right sides, with respect to the lateral center line La of the toilet body 12, and the left portion 18-L of the rim part 18 means a portion located on the left side, as the other of left and right sides, with respect to the lateral center line La.

To the left water passage 32-L and the right water passage 32-R, flush water is supplied from a flush water supply device 36, which is not illustrated. The flush water supply device 36 of the present embodiment is configured by combining a flush water tank, a distributor, and the like. FIG. 2 shows directions Wp1 in which flush water is supplied from the flush water supply device 36 to the water passages 32, and directions Wp2 in which flush water flows within the water passages 32.

The right water passage 32-R is formed, as a whole, to extend in the counterclockwise direction inside the right portion 18-R of the rim part 18, and the first discharge outlet 30-A is provided on the end side of the extending direction.

The left water passage 32-L is formed, as a whole, to extend in the clockwise direction inside the left portion 18-L of the rim part 18, and the second discharge outlet 30-B is provided on the end side of the extending direction. The left water passage 32-L includes an extending part 38 that extends in the longitudinal direction of the toilet body 12 inside the left portion 18-L of the rim part 18, and a turning part 40 provided continuously with the front end side of the extending part 38. The turning part 40 is provided to lead the flush water flowing from the extending part 38 in the clockwise direction to turn toward the counterclockwise direction. The turning part 40 leads the flush water such that the position of the flow of flush water is changed from the outside to the inside in radial directions of the toilet bowl part 14. The left water passage 32-L also includes a branch part 42, which is formed to branch off from the rear end part of the extending part 38 as a path extending from the starting end side toward the termination end side of the extending part 38 and which extends in the counterclockwise direction. On the end side of the extending direction of the branch part 42, the third discharge outlet 30-C is provided. In the left water passage 32-L of the present embodiment, flush water supplied from the flush water supply device flows into the rear end part of the extending part 38.

On the inner peripheral wall part 18 a of the rim part 18, the three rim conduits 44 are formed such as to extend from the respective three discharge outlets 30 in the counterclockwise direction. The rim conduits 44 are provided to receive, at shelf parts 46, flush water discharged through the discharge outlets 30 and to lead the flush water to swirl in the counterclockwise direction, so that the flush water is easily delivered from the starting end position to the termination end position of each rim conduit 44.

The three rim conduits 44 are respectively provided for the three discharge outlets 30 and include a first rim conduit 44-A for the first discharge outlet 30-A, a second rim conduit 44-B for the second discharge outlet 30-B, and a third rim conduit 44-C for the third discharge outlet 30-C. The first rim conduit 44-A is formed to extend, in the counterclockwise direction in plan view, from the first discharge outlet 30-A to a termination end position, which is located near the second discharge outlet 30-B and on the radially inner side with respect to the second discharge outlet 30-B. Also, the second rim conduit 44-B is formed to extend in the counterclockwise direction from the second discharge outlet 30-B to a termination end position, which is located near the third discharge outlet 30-C and on the radially inner side with respect to the third discharge outlet 30-C. The starting end part of the second rim conduit 44-B is formed continuously with the termination end part of the first rim conduit 44-A. The third rim conduit 44-C is formed to extend, in the counterclockwise direction in plan view, from the third discharge outlet 30-C to a termination end position, which is located near the first discharge outlet 30-A and on the radially inner side with respect to the first discharge outlet 30-A.

As shown in FIGS. 1 and 2, the first rim conduit 44-A includes a first shelf part 46-A for receiving flush water, and a first overhang part 48-A provided above the first shelf part 46-A. The first shelf part 46-A is formed to have a gradient that is gentler than the inner peripheral surface portion of the receiving surface part 22 (the inner peripheral surface portion of the toilet bowl part 14) provided continuously with the lower side of the first shelf part 46-A. The first overhang part 48-A is formed to extend radially inward of the toilet bowl part 14. Also, the second rim conduit 44-B includes a second shelf part 46-B and a second overhang part (not illustrated) having configurations similar to those of the first shelf part 46-A and the first overhang part 48-A in the first rim conduit 44-A. Further, the third rim conduit 44-C includes a third shelf part 46-C and a third overhang part 48-C having configurations similar to those of the first shelf part 46-A and the first overhang part 48-A in the first rim conduit 44-A.

As shown in FIG. 2, in the third rim conduit 44-C, a flow changing part 50 is provided at a position on which the direction of flush water discharged through the third discharge outlet 30-C hits. The flow changing part 50 is part of a wall part 52 that separates the internal space of the toilet bowl part 14 and the right water passage 32-R. The flow changing part 50 is provided to change, by allowing the flush water discharged through the third discharge outlet 30-C to hit on the flow changing part 50, the flow direction of the flush water to the direction toward the recess part 24 of the toilet bowl part 14.

The water discharge part 20 of the flush toilet 10 described above is configured such that the largest amount of flush water is discharged through the first discharge outlet 30-A, the second largest amount of flush water is discharged through the third discharge outlet 30-C, and the smallest amount of flush water is discharged through the second discharge outlet 30-B. Namely, the water discharge part 20 is configured such that the amounts of flush water discharged through the first discharge outlet 30-A, the third discharge outlet 30-C, and the second discharge outlet 30-B decrease in this order. In the present embodiment, the ratio of the amounts of flush water discharged through the respective discharge outlets 30 may be 40:27:33, for example. The amount of flush water discharged means a flow volume of flush water discharged through a discharge outlet 30 per unit time (L/s).

In order to satisfy such magnitude relationships among the amounts of flush water discharged through the respective discharge outlets 30, the water discharge part 20 of the present embodiment is configured as described below. Here is considered a water path of flush water in each water passage 32, from the inlet position, to which the flush water is provided from the flush water supply device, to each discharge outlet 30. There are water paths respectively provided for the first discharge outlet 30-A through the third discharge outlet 30-C. The amount of flush water discharged through a discharge outlet is proportional to the passage cross-sectional area of a portion (hereinafter, referred to as a flow rate setting part) of which the passage cross-sectional area is smallest in the water path for supplying flush water to the discharge outlet. In the present embodiment, the flow rate setting part for the first discharge outlet 30-A is the first discharge outlet 30-A itself located at the downstream end of the water path for the first discharge outlet 30-A. Also, the flow rate setting part for the second discharge outlet 30-B is the second discharge outlet 30-B itself, and the flow rate setting part for the third discharge outlet 30-C is the third discharge outlet 30-C itself. The water discharge part 20 is configured such that the passage cross-sectional area of the flow rate setting part for the first discharge outlet 30-A is largest, that for the third discharge outlet 30-C is second largest, and that for the second discharge outlet 30-B is smallest. The passage cross-sectional area means the cross-sectional area of a cross section perpendicular to the water flowing direction. Accordingly, the aforementioned magnitude relationships among the amounts of flush water discharged through the respective discharge outlets 30 can be satisfied.

In the following, a method for flushing the toilet bowl part 14 in the flush toilet 10 set forth above will be described.

In the flush toilet 10, the inside of the toilet bowl part 14 is flushed using a flushing method of the so-called wash-down type in which waste within the toilet bowl part 14 is flushed away into the drainage passage part 16 by means of a fall of water. By operating an operation member, such as a switch and a lever, to start supply of flush water, flush water is supplied from the flush water supply device within a predetermined flow rate range. In the following, an operation from the start through the end of supply of flush water within a predetermined flow rate range will be described as one flushing operation.

Flush water is supplied from the flush water supply device to each of the right water passage 32-R and the left water passage 32-L. Within the right water passage 32-R, the flush water supplied from the flush water supply device flows to be led to the first discharge outlet 30-A. Within the left water passage 32-L, part of the flush water supplied from the flush water supply device flows through the extending part 38 and the turning part 40 to be led to the second discharge outlet 30-B, and other part of the flush water flows through the branch part 42 to be led to the third discharge outlet 30-C. As a result, the flush water flowing through the respective water passages 32 is discharged through the respective discharge outlets 30.

FIG. 4 is a diagram that shows flows of flush water within the toilet bowl part 14. In FIG. 4, flows of flush water within the toilet bowl part 14 are indicated by arrows.

The flush water discharged through the first discharge outlet 30-A through the third discharge outlet 30-C forms flows Fa through Fc swirling in the counterclockwise direction respectively along the first rim conduit 44-A through the third rim conduit 44-C. The flush water flowing along each of the first rim conduit 44-A through the third rim conduit 44-C gradually flows down through the shelf part 46 of the rim conduit 44 to the receiving surface part 22, so as to form flows Fd and Fe flowing toward the lower side of the receiving surface part 22 while swirling. In this way, the water discharge part 20 discharges flush water into the toilet bowl part 14 through the discharge outlets 30-A through 30-C, so as to form the flows Fa through Fe swirling in the counterclockwise direction within the toilet bowl part 14. The flows Fa through Fe are flows of water used to flush the inner peripheral surface of the toilet bowl part 14, more specifically the inner peripheral surface of the rim part 18 and the inner peripheral surface of the receiving surface part 22.

On the inner peripheral surface of the toilet bowl part 14, a large curvature portion 22 a is provided on the lateral center line La, on the front side with respect to the recess part 24. The large curvature portion 22 a is generally a portion of which the curvature is larger than other portions provided continuously on the left and right sides of the toilet bowl part 14 in plan view. When the flow Fa formed by the flush water discharged through the first discharge outlet 30-A flows through the large curvature portion 22 a, the velocity component of the flush water in the circumferential direction of the toilet bowl part 14 is reduced, thereby forming a flow Fg that intensively flows into the recess part 24. The flow Fg becomes a main flow Fg (water flux) of which the flow rate is greater than the flow rates of other nearby flows, and the flow Fg flows from the front side toward the rear side in the toilet bowl part 14. Also, the main flow Fg flows into the recess part 24 from an oblique front side with respect to the recess part 24. The waste within the recess part 24 of the toilet bowl part 14 is flushed away into the drainage passage part 16 through the inlet 16 a by means of a fall of flush water flowing on the receiving surface part 22 or the rim conduits 44 in the toilet bowl part 14, particularly a fall of flush water included in the main flow Fg.

The flush water discharged through the third discharge outlet 30-C flows through the third rim conduit 44-C and hits on the flow changing part 50, thereby changing its flow direction and forming a flow Fh that flows from the rear side to the front side toward the inside of the recess part 24. Since the flow Fh does not flow through the large curvature portion 22 a of the toilet bowl part 14, the flow Fh is likely to flow into the recess part 24 while keeping the strong force of the flush water discharged through the third discharge outlet 30-C. The flow Fh with the strong force changes its flow direction such as to turn from the front side toward the rear side within the recess part 24 and then flows into the drainage passage part 16 via the inlet 16 a. At the time, since the flow Fh merges with the main flow Fg formed by the flush water discharged through the first discharge outlet 30-A, the force of the flow of water flowing into the drainage passage part 16 via the inlet 16 a is increased, so that the waste discharge capability can be effectively improved. Although not illustrated, part of the flush water discharged through the third discharge outlet 30-C flows from the rear side toward the front side at the right of the recess part 24 and flows through the large curvature portion 22 a of the toilet bowl part 14 to merge into the aforementioned main flow Fg on the receiving surface part 22 of the toilet bowl part 14, thereby increasing the force of the flow of water.

There will now be described effects of the flush toilet 10 set forth above.

(A) The first discharge outlet 30-A of the present embodiment is provided in the first divided region Sr1. Accordingly, the flush water discharged through the first discharge outlet 30-A flows through the large curvature portion 22 a of the toilet bowl part 14, so that the velocity component of the flush water in the circumferential direction of the toilet bowl part 14 is reduced. Owing to the influence thereof, the flush water discharged through the first discharge outlet 30-A is less likely to reach the receiving surface part 22 and the rim conduit 44 in the fourth divided region Sr4. As a countermeasure thereto, in the flush toilet 10 of the present embodiment, the second discharge outlet 30-B is provided in the third divided region Sr3. Accordingly, a sufficient amount of flush water can be easily provided to the fourth divided region Sr4 where the flush water discharged through the first discharge outlet 30-A is less likely to reach, so that favorable toilet bowl flushing capability can be obtained.

Especially, since increase of the total amount of flush water used for one toilet flushing process is unnecessary to obtain such an effect, there is the advantage of obtaining favorable toilet bowl flushing capability while preventing splash out of flush water due to increase of the total amount of flush water.

Also, the water discharge part 20 is configured such that the amount of flush water discharged through the first discharge outlet 30-A is larger than the amount of flush water discharged through the second discharge outlet 30-B. Accordingly, there is the advantage that the size of the left water passage 32-L, formed inside the rim part 18 to supply flush water to the second discharge outlet 30-B, can be reduced, so that the toilet bowl flushing capability can be improved without increasing the width of the rim part 18.

As described previously, the waste discharge performance can be ensured by the main flow Fg formed by the flush water discharged through the first discharge outlet 30-A. Accordingly, because a large amount of flush water need not be ensured to flush the fourth divided region Sr4, even though the amount of flush water discharged through the second discharge outlet 30-B is small, the waste discharge performance will not be significantly affected.

(B) The discharge outlets of the present embodiment include the third discharge outlet 30-C provided in the fourth divided region Sr4. Accordingly, flush water can be easily delivered to the vicinity of the first discharge outlet 30-A positioned distantly from the second discharge outlet 30-B in the counterclockwise direction within the toilet bowl part 14, without increasing the amount of flush water discharged through the second discharge outlet 30-B. Therefore, a large area of the toilet bowl part 14 can be easily flushed, while the amount of flush water discharged through the second discharge outlet 30-B can be reduced.

Also, the flush water discharged through the third discharge outlet 30-C provided in the fourth divided region Sr4 merges, within the recess part 24 and on the receiving surface part 22, with the flush water discharged through the first discharge outlet 30-A, thereby increasing the force of the main flow Fg contributing to the waste discharge capability. Since the water discharge part 20 of the present embodiment is configured such that the amount of flush water discharged through the third discharge outlet 30-C is equal to or larger than the amount of flush water discharged through the second discharge outlet 30-B, by effectively increasing the force of the main flow Fg, the waste discharge capability can also be effectively improved.

Also, the layout of the flush toilet 10 is such that the right water passage 32-R for supplying flush water to the first discharge outlet 30-A and the left water passage 32-L for supplying flush water to the second discharge outlet 30-B are separately provided in the right portion 18-R and the left portion 18-L of the rim part 18, respectively. Accordingly, compared to the case where both the right water passage 32-R and the left water passage 32-L are provided in one side portion of the rim part 18, the width of the rim part 18 need not be made larger. Also, since the left water passage 32-L is provided with the turning part 40, the directions of flush water discharged through the first discharge outlet 30-A and the second discharge outlet 30-B can be made identical (the counterclockwise direction), even with such a layout.

In the following, other features of the flush toilet 10 of the present embodiment will be described. FIG. 5 is a plan view that shows a magnified view of vicinity of the second discharge outlet 30-B.

The first rim conduit 44-A includes a front end part 53 that passes through the front end 14F of the toilet bowl part 14, and a termination end part 54 located downstream of the front end part 53 along the first rim conduit 44-A. The front end 14F of the toilet bowl part 14 is a position at which the aforementioned lateral center line La and the inner peripheral surface of the toilet bowl part 14 intersect in plan view. The termination end part 54 of the first rim conduit 44-A is located on the radially inner side of the toilet bowl part 14 with respect to the turning part 40, which is the downstream end part of the left water passage 32-L.

In plan view, the radius of curvature of the inner peripheral surface of the termination end part 54 in the first rim conduit 44-A is defined as A, and the radius of curvature of the inner peripheral surface of a starting end part 56 in the second rim conduit 44-B is defined as B. The front end part 53 and the termination end part 54 of the first rim conduit 44-A and the starting end part 56 of the second rim conduit 44-B are indicated by hatching in FIG. 5. The termination end part 54 of the first rim conduit 44-A is formed such as to be smaller in radius of curvature of the inner peripheral surface than the starting end part 56 of the second rim conduit 44-B in plan view. Namely, the radius of curvature A of the termination end part 54 of the first rim conduit 44-A is smaller than the radius of curvature B of the starting end part 56 of the second rim conduit 44-B. The radius of curvature A may be equal to or greater than 40 mm and less than 80 mm, and the radius of curvature B may be in the range of 300 mm to 600 mm, for example. Advantages thereof will be described.

As described previously with reference to FIG. 4, the flow Fe formed by the flush water discharged through the first discharge outlet 30-A forms the main flow Fg that intensively flows into the recess part 24. The flow forming the main flow Fg includes the flow Fa that flows from the first discharge outlet 30-A through the first rim conduit 44-A. According to the present embodiment, the radius of curvature of the termination end part 54 of the first rim conduit 44-A and the radius of curvature of the starting end part 56 of the second rim conduit 44-B satisfy the aforementioned relationship. Accordingly, compared to the case where the radii of curvature are the same, the flow of flush water flowing away from a termination end position 54 a on the inner peripheral surface of the first rim conduit 44-A after flowing along the first rim conduit 44-A can be directed to the recess part 24 more easily. This means that, viewed from the termination end position 54 a of the first rim conduit 44-A, the flow of flush water can be directed toward the center point Cp of the toilet bowl part 14 more easily. As a result, the amount of flush water included in the main flow Fg, which intensively flows into the recess part 24, is increased, so that the waste discharge performance can be effectively improved.

Also, in plan view, the radius of curvature of the inner peripheral surface of the front end part 53 in the first rim conduit 44-A is defined as C. The termination end part 54 of the first rim conduit 44-A is formed such as to be smaller in radius of curvature of the inner peripheral surface than the front end part 53 of the first rim conduit 44-A in plan view. Namely, the radius of curvature A of the termination end part 54 of the first rim conduit 44-A is smaller than the radius of curvature C of the front end part 53 of the first rim conduit 44-A. The radius of curvature C may be in the range from 80 mm to 120 mm inclusive, for example.

Accordingly, compared to the case where the radii of curvature are the same, the flow of flush water flowing away from a termination end position 54 a on the inner peripheral surface of the first rim conduit 44-A after flowing along the first rim conduit 44-A can be directed to the recess part 24 more easily. As a result, the amount of flush water included in the main flow Fg, which intensively flows into the recess part 24, is increased, so that the waste discharge performance can be effectively improved.

Although an example has been described in the present embodiment in which the entirety of the termination end part 54 of the first rim conduit 44-A is smaller in radius of curvature than the starting end part 56 of the second rim conduit 44-B, at least part of the termination end part 54 may satisfy the condition. Similarly, although an example has been described in which the entirety of the termination end part 54 of the first rim conduit 44-A is smaller in radius of curvature than the front end part 53 of the first rim conduit 44-A, at least part of the termination end part 54 may satisfy the condition. For example, only part of the termination end part 54 of the first rim conduit 44-A, positioned upstream of the termination end position 54 a of the first rim conduit 44-A and downstream of the front end part 53 of the first rim conduit 44-A, may satisfy the condition.

An exemplary embodiment of the present invention has been described in detail. The abovementioned embodiment merely describes a specific example for carrying out the present invention. The embodiment is not intended to limit the technical scope of the present invention, and various modifications may be made to the embodiment without departing from the scope of ideas of the invention defined in the claims. Also, the hatching provided on the cross sections in the drawings is not provided to limit the materials of the objects with the hatching.

Although the wash-down type is described as an example of the flushing method for the flush toilet 10, the inside of the toilet bowl part 14 may be flushed using a flushing method combined with another type, such as the siphon type and the siphon jet type.

Although an example has been described in which the first discharge outlet 30-A is provided in the second divided region Sr2, the first discharge outlet 30-A has only to be provided in at least one of the first divided region Sr1 and the second divided region Sr2. Also, in terms of obtaining the aforementioned effect (A), providing the three discharge outlets 30 is not essential, and it is acceptable as long as at least the first discharge outlet 30-A and the second discharge outlet 30-B are provided.

Although an example has been described in which the left water passage 32-L and the right water passage 32-R are provided at spatially separated positions, those water passages may communicate with each other via a common water passage. In this case, flush water supplied from the flush water supply device is supplied to each of the left water passage 32-L and the right water passage 32-R via the common water passage.

With regard to the water discharge part 20, it may be acceptable as long as the largest amount of flush water is discharged through the first discharge outlet 30-A, and a specific example thereof is not particularly limited. For example, the ratio of the amounts of flush water discharged through the first discharge outlet 30-A, the second discharge outlet 30-B, and the third discharge outlet 30-C may be set to 40:25:35 or 60:3:37, besides 40:27:33. From these examples, it can be said that the water discharge part 20 may be configured such that the proportion of the amount of flush water discharged through the first discharge outlet 30-A to the total amount of flush water used for one flushing operation is 40 percent or greater.

Also, the ratio of the amounts of flush water discharged through the respective discharge outlets 30 may be set to 50:25:25, for example, so that the amounts of flush water discharged through the second discharge outlet 30-B and the third discharge outlet 30-C are equal to each other. Namely, the water discharge part 20 may be configured such that the amount of flush water discharged through the third discharge outlet 30-C is equal to or larger than the amount of flush water discharged through the second discharge outlet 30-B. In either case, the aforementioned effect (B) can be obtained.

Although an example has been described in which each of the shelf parts 46 of the rim conduits 44 is formed into a planar shape, it may be formed into an arc shape or the like. Also, the rim conduits 44 need not necessarily include the overhang parts 48. Also, although an example has been described in which the first rim conduit 44-A is formed continuously with the second rim conduit 44-B, they may be formed separately, instead of continuously.

When the inventions embodied by the embodiment and modifications set forth above are generalized, the following technical ideas are derived. In the following, description will be made using the aspect described in PROBLEM(S) TO BE SOLVED BY THE INVENTION.

In a flush toilet of the second aspect, in the first aspect: the rim part may include a first rim conduit that receives, at a first shelf part, flush water discharged through the first discharge outlet and leads the flush water, and a second rim conduit that receives, at a second shelf part, flush water discharged through the second discharge outlet and leads the flush water; a termination end part of the first rim conduit may be located on the radially inner side of the toilet bowl part with respect to a downstream end part of a water passage for supplying flush water to the second discharge outlet; and at least part of the termination end part of the first rim conduit may be formed such as to be smaller in radius of curvature of the inner peripheral surface than a starting end part of the second rim conduit in plan view.

The flush water discharged through the first discharge outlet forms a main flow that intensively flows into a recess part. According to this aspect, compared to the case where at least part of the termination end part of the first rim conduit is identical in radius of curvature with the starting end part of the second rim conduit, the flow of flush water flowing away from a termination end position of the first rim conduit after flowing along the first rim conduit can be directed to the recess part more easily. As a result, the amount of flush water included in the main flow, which intensively flows into the recess part, is increased, so that the waste discharge performance can be effectively improved.

In a flush toilet of the third aspect, in the first and second aspects: the rim part may include a first rim conduit that receives, at a first shelf part, flush water discharged through the first discharge outlet and leads the flush water; the first rim conduit may include a front end part that passes through a front end of the toilet bowl part, and a termination end part provided downstream of the front end part along the first rim conduit and located on the radially inner side of the toilet bowl part with respect to a downstream end part of a water passage for supplying flush water to the second discharge outlet; and at least part of the termination end part of the first rim conduit may be formed such as to be smaller in radius of curvature of the inner peripheral surface than the front end part in plan view.

The flush water discharged through the first discharge outlet forms a main flow that intensively flows into a recess part. According to this aspect, compared to the case where at least part of the termination end part of the first rim conduit is identical in radius of curvature with the front end part of the first rim conduit, the flow of flush water flowing away from a termination end position of the first rim conduit after flowing along the first rim conduit can be directed to the recess part more easily. As a result, the amount of flush water included in the main flow, which intensively flows into the recess part, is increased, so that the waste discharge performance can be effectively improved.

In a flush toilet of the fourth aspect, in the first through third aspects: the plurality of discharge outlets may include a third discharge outlet provided in the fourth divided region; and the water discharge part may be configured such that the amount of flush water discharged through the third discharge outlet is equal to or larger than the amount of flush water discharged through the second discharge outlet.

According to this aspect, flush water can be easily delivered to a position distant from the second discharge outlet in one circumferential direction, without increasing the amount of flush water discharged through the second discharge outlet. Therefore, a large area of the toilet bowl part can be easily flushed, while the amount of flush water discharged through the second discharge outlet can be reduced.

In a flush toilet of the fifth aspect, in any one of the first through fourth aspects, the water discharge part may include: a first water passage that is formed inside a first portion, on which the first discharge outlet is provided, of right and left portions of the rim part and that supplies flush water to the first discharge outlet; and a second water passage that is formed inside a second portion, on which the second discharge outlet is provided, of the right and left portions of the rim part, that is provided with a turning part for leading flush water flowing in the other circumferential direction to turn toward the one circumferential direction, and that supplies flush water to the second discharge outlet.

According to this aspect, the layout of the flush toilet can be made such that the first water passage and the second water passage are separately provided in the first portion and the second portion of the rim part, respectively. Accordingly, compared to the case where both the first water passage and the second water passage are provided in one side portion of the rim part, the width of the rim part need not be made larger.

EXPLANATION OF REFERENCE NUMERALS

-   -   Sr1 first divided region     -   Sr2 second divided region     -   Sr3 third divided region     -   Sr4 fourth divided region     -   10 flush toilet     -   12 toilet body     -   14 toilet bowl part     -   18 rim part     -   20 water discharge part     -   30-A first discharge outlet     -   30-B second discharge outlet     -   30-C third discharge outlet     -   32 water passage     -   44-A first rim conduit     -   44-B second rim conduit     -   46-A first shelf part     -   46-B second shelf part

The present invention relates to a flush toilet. 

1. A flush toilet, comprising a toilet body including a toilet bowl part, a rim part that forms a peripheral edge part of an upper opening of the toilet bowl part, and a water discharge part that discharges flush water into the toilet bowl part, wherein: the water discharge part includes a plurality of discharge ports formed in the rim part and provided to discharge flush water in one circumferential direction along an inner peripheral surface of the rim part; when the toilet bowl part is divided into four divided regions in plan view by a lateral center line, which bisects a lateral dimension of an outer surface portion of the toilet body, and a longitudinal center line, which bisects a longitudinal dimension of an inner surface portion of the toilet bowl part, and when, with regard to the four divided regions, a rear-side divided region to which a front-side divided region is adjacent in the other circumferential direction is defined as a first divided region, and the three divided regions located subsequent to the first divided region in the one circumferential direction are serially defined as a second divided region, a third divided region, and a fourth divided region, the plurality of discharge outlets include a first discharge outlet provided in at least one of the first divided region and the second divided region, and a second discharge outlet provided in the third divided region; and the water discharge part is configured such that the amount of flush water discharged through the first discharge outlet is larger than the amount of flush water discharged through the second discharge outlet.
 2. The flush toilet of claim 1, wherein: the rim part includes a first rim conduit that receives, at a first shelf part, flush water discharged through the first discharge outlet and leads the flush water, and a second rim conduit that receives, at a second shelf part, flush water discharged through the second discharge outlet and leads the flush water; a termination end part of the first rim conduit is located on a radially inner side of the toilet bowl part with respect to a downstream end part of a water passage for supplying flush water to the second discharge outlet; and at least part of the termination end part of the first rim conduit is formed such as to be smaller in radius of curvature of the inner peripheral surface than a starting end part of the second rim conduit in plan view.
 3. The flush toilet of claim 1, wherein: the rim part includes a first rim conduit that receives, at a first shelf part, flush water discharged through the first discharge outlet and leads the flush water; the first rim conduit includes a front end part that passes through a front end of the toilet bowl part, and a termination end part located downstream of the front end part along the first rim conduit and located on the radially inner side of the toilet bowl part with respect to a downstream end part of a water passage for supplying flush water to the second discharge outlet; and at least part of the termination end part of the first rim conduit is formed such as to be smaller in radius of curvature of the inner peripheral surface than the front end part in plan view.
 4. The flush toilet of claim 1, wherein: the plurality of discharge outlets include a third discharge outlet provided in the fourth divided region; and the water discharge part is configured such that the amount of flush water discharged through the third discharge outlet is equal to or larger than the amount of flush water discharged through the second discharge outlet.
 5. The flush toilet of claim 1, wherein the water discharge part includes: a first water passage that is formed inside a first portion, on which the first discharge outlet is provided, of right and left portions of the rim part and that supplies flush water to the first discharge outlet; and a second water passage that is formed inside a second portion, on which the second discharge outlet is provided, of the right and left portions of the rim part, that is provided with a turning part for leading flush water flowing in the other circumferential direction to turn toward the one circumferential direction, and that supplies flush water to the second discharge outlet.
 6. The flush toilet of claim 2, wherein: the rim part includes a first rim conduit that receives, at a first shelf part, flush water discharged through the first discharge outlet and leads the flush water; the first rim conduit includes a front end part that passes through a front end of the toilet bowl part, and a termination end part located downstream of the front end part along the first rim conduit and located on the radially inner side of the toilet bowl part with respect to a downstream end part of a water passage for supplying flush water to the second discharge outlet; and at least part of the termination end part of the first rim conduit is formed such as to be smaller in radius of curvature of the inner peripheral surface than the front end part in plan view.
 7. The flush toilet of claim 2, wherein: the plurality of discharge outlets include a third discharge outlet provided in the fourth divided region; and the water discharge part is configured such that the amount of flush water discharged through the third discharge outlet is equal to or larger than the amount of flush water discharged through the second discharge outlet.
 8. The flush toilet of claim 3, wherein: the plurality of discharge outlets include a third discharge outlet provided in the fourth divided region; and the water discharge part is configured such that the amount of flush water discharged through the third discharge outlet is equal to or larger than the amount of flush water discharged through the second discharge outlet.
 9. The flush toilet of claim 2, wherein the water discharge part includes: a first water passage that is formed inside a first portion, on which the first discharge outlet is provided, of right and left portions of the rim part and that supplies flush water to the first discharge outlet; and a second water passage that is formed inside a second portion, on which the second discharge outlet is provided, of the right and left portions of the rim part, that is provided with a turning part for leading flush water flowing in the other circumferential direction to turn toward the one circumferential direction, and that supplies flush water to the second discharge outlet.
 10. The flush toilet of claim 3, wherein the water discharge part includes: a first water passage that is formed inside a first portion, on which the first discharge outlet is provided, of right and left portions of the rim part and that supplies flush water to the first discharge outlet; and a second water passage that is formed inside a second portion, on which the second discharge outlet is provided, of the right and left portions of the rim part, that is provided with a turning part for leading flush water flowing in the other circumferential direction to turn toward the one circumferential direction, and that supplies flush water to the second discharge outlet.
 11. The flush toilet of claim 4, wherein the water discharge part includes: a first water passage that is formed inside a first portion, on which the first discharge outlet is provided, of right and left portions of the rim part and that supplies flush water to the first discharge outlet; and a second water passage that is formed inside a second portion, on which the second discharge outlet is provided, of the right and left portions of the rim part, that is provided with a turning part for leading flush water flowing in the other circumferential direction to turn toward the one circumferential direction, and that supplies flush water to the second discharge outlet. 